I’m old enough to remember when American liberals cherished the freedom of speech guaranteed by the First Amendment. They celebrated especially the freedom accorded those with unpopular beliefs and protested attempts to squelch the expression of differing opinions.

Today, things are different. American liberals are not challenging the Supreme Court rulings extending First Amendment protection to nude dancers, flag burners, and students wearing antiwar armbands. They are content to leave these as forms of protected free speech.

But political speech is a whole other thing. Currently, 43 Democratic senators are co-sponsoring the constitutional amendment introduced by New Mexico’s Sen. Tom Udall to amend the First Amendment so that it no longer protects political speech.

“To protect the integrity of the legislative and electoral processes,” the text reads, “Congress shall have power to regulate the raising and spending of money and in-kind equivalents with respect to federal elections,” including limits on contributions to and spending by or against candidates. The same power is given to state governments.

Delphically, the amendment adds, “Nothing in this article shall be construed to grant Congress the power to abridge the freedom of the press.” So the New York Times can keep commenting on elections. Maybe bloggers can, too. (Are they the press?)

But if you want to run an ad on television or send out a mailing opposing a candidate’s stand on an issue, these 43 Democratic senators want to shut you down.

Too much conversation could muddy the waters, apparently. And note that spending against a candidate can be barred (incumbents hate well-financed challengers) and that “in-kind equivalents” — gas money to circulate petitions? shoe leather? — can be limited.

Many Democrats have been hopping mad about the exercise of free political speech since the Supreme Court’s 2010 Citizens United decision. That’s the case President Obama criticized in front of several justices in his 2011 State of the Union address.

Citizens United is a corporation that produced something called “Hillary: The Movie” and wanted to show it within 30 days of the 2008 Democratic primaries. The lower courts said this violated the 2002 McCain-Feingold limitations on “electioneering communications.” The Supreme Court said it was free speech, protected by the First Amendment.

Over the years, supporters of campaign finance regulation (not all of them Democrats) have argued that spending money is not speech. But it’s hard to think of any way of communicating your ideas to others, even over the Internet, without spending money.

A louder response to Citizens United is that it is preposterous to say that corporations have a right to free speech. Only individuals do. Which, I suppose, means that the New York Times could be restricted as long as it’s a corporation–but not if it were personally owned by Arthur O. Sulzberger, Jr.

This is not the only example of liberals trying to squelch unwelcome speech. Read the Lois Lerner Internal Revenue Service emails that someone somehow didn’t manage to destroy, and you see a liberal self-righteously determined to silence opponents.